The name given to the noise made by the brakes when they are just slipping when starting (or stopping) from rest. The brake graunch is mainly exhibited on the vehicles fitted with automatic transmission, but can also occur on manual vehicles e.g., on a steep hill. It is caused by brake pad stick-slip when static and dynamic friction is very similar. The term 'creep/groan' is also used to describe the brake graunch.

Brake judder is the phenomenon where with medium to heavy braking from high speed, severe vibration is felt throughout the whole vehicle. It is often attributed to a mode of vibration in which the front suspension executes a predominantly fore and aft vibration with the two road wheels in-phase with each other. Excitation is often provided by the oscillatory forcing generated when applying the brakes to a brake disk that has disk thickness variation.

Unpolarised light can be polarised by reflection. When unpolarised light is reflected from the surface of an optical material (glass, say) then preferential reflection occurs for the electric-field vector that is perpendicular to plane of incidence.